Change in the cellular localization of alkaline phosphatase by alteration of its carboxy-terminal sequence.
Alkaline phosphatase (AP) is secreted into the medium when the carboxy-terminal 25 amino acids are replaced by the 60 amino acid carboxy-terminal signal peptide (HlyAs) of Escherichia coli haemolysin (HlyA). Secretion of the AP-HlyAs fusion protein is dependent on HlyB and HlyD but independent of SecA and SecY. The efficiency of secretion by HlyB/HlyD is decreased when AP carries its own N-terminal signal peptide. Translocation of this fusion protein into the periplasm is not observed even in the absence of HlyB/HlyD. The failure of the Sec export machinery to transport the latter protein into the periplasm seems to be due in part to the loss of the carboxy-terminal sequence of AP since even AP derivatives which do not carry the HlyA signal peptide but lack the 25 C-terminal amino acids of AP are localized in the membrane but not translocated into the periplasm.
Gentschev
I
I
Institut für Genetik und Mikrobiologie, Universität Würzburg, Federal Republic of Germany.
Hess
J
J
Goebel
W
W
D000469:Alkaline Phosphatase / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005798:Genes, Bacterial; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008969:Molecular Sequence Data; D010957:Plasmids; D021382:Protein Sorting Signals / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D015183:Restriction Mapping
D001426:Bacterial Proteins; D006460:Hemolysin Proteins; D008565:Membrane Proteins; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins; D000469:Alkaline Phosphatase